This invention relates generally to audio signal processing, and more particularly the present invention relates to a display device which indicates musical notes representing varying pitch of an input audio signal on a screen of a display unit.
Musical note display devices, which are capable of indicating musical notes on a staff of a music sheet in accordance with input audio signals from a musical instrument, have been desired since such a device is useful for composing or writing music and for music education. Various devices have been made previously for indicating musical notes, and a conventional device of this sort is simply arranged to selectively energize lamps on a board on which a staff of a musical sheet is indicated, in accordance with electrical signals produced by a keyboard. However, such a conventional display device cannot handle sounds emitted from musical instruments which do not have a keyboard, such as stringed instruments or wind instruments. Therefore, in other conventional display devices, sounds from musical instruments are first converted into an electrical signal, and frequency analysis is effected by using a number of band pass filters so as to determine the pitch to be displayed by way of a lamp selected from a plurality of lamps on a staff-like board or a display panel. However, such a conventional musical note display device requires a number of band pass filters, and therefore it suffers from having a complex structure.